musculature --> knee Flashcards
extensors
quadriceps femoris
–> vastus lateralis, vastus intermedius, vastus medialis, rectus femoris
vastus medialis is divided into
vastus medialis longus
vastus medialis oblique
where does the VMO insert into the patella
50-55 degree angle
important for patellar tracking
how does the muscles attach
converge and insert on the patella via the quadriceps tendon
then the patella is attached to the tibial tubercle via the patellar ligament
rectus femoris
2 joint muscle
susceptible to active and passive insufficiencies
articularis genu
not an extensor, but important during active knee extension
attaches to the superior knee joint capsule
pulls the synovial membrane of the knee joint upwards to prevent impingement of the suprapatellar pouch b/w the tibiofemoral joint during knee extension
felxors
semimembranosus
semitendinosus
biceps femoris
sartorius
gracilis
popliteus
gastrocnemius
semimembranosus
deforms medial meniscus posteriorly during knee flexion
sartorius
role at the hip more important
gracilis
readily becomes actively insufficient
popliteus
attaches to the lateral meniscus and will pull the lateral meniscus posteriorly to allow full knee flexion
“unlocks” the knee
gastrocnemius
weak knee flexor
effective in preventing knee joint hyperextension
dynamic stabilizer of the knee (especially during final stages of single-limb support during walking)
internal rotators of the tibia
semimembranosus
semitendinosus
gracilis
popliteus
sartorius
external rotation of the tibia
biceps femoris
TFL (will flex and ER the tibia)
gait
primary function of the knee during gait is to adjust the length of the lower extremity to allow ground clearance
during swing phase of gait